The Behavior of Tropical Ozone During the Stratospheric Warming of March–April 1976

Abstract

The backscatter ultraviolet spectrometer on the Atmosphere Explorer-E satellite obtained ozone data for the upper stratosphere and lower mesosphere from an equatorial orbit near the time of the March?April 1976 stratospheric warming. A simple inversion technique allows the extraction of information on the absolute ozone (O3) abundance and its longitudinal variation from the measured radiances. Between altitudes of 35 and 60 km tropical O3 in constant pressure layers exhibits increased spatial variations on length scales of 20° to 30° in longitude after the onset of the polar warming, indicating enhanced wave activity. One week after the polar vortex breakdown upper stratospheric O3 begins a relaxation toward the unperturbed state, while that in the lower mesosphere continues to show maximum variations near ±10% of the longitudinally averaged value. Although the degree of horizontal structure increases during the warming, the absolute O3 amounts averaged over longitude between 35 and 60 km in altitude remain nearly constant in time. The observed behavior is consistent with that expected from enhanced vertical transport of O3 in the tropics with accompanying adiabatic temperature changes which alter the chemical loss rate.